A large number of wall structures and forms have been devised to reduce the time and cost of fabricating walls and foundation systems. These structures are typically comprised of opposing pairs of polymer panels which are held apart with an imaginative and often complex variety of ties and spacers. The panels incorporate a number of designs that permit adjoining panels to be interlocked in both horizontal and vertical directions to allow wall forms of varying lengths and heights to be assembled. Such polymer panels may be used to construct both structural and non-load beating walls. The panels may serve as forms for pouring concrete walls, after which the panels may either be left in place or removed, or they may simply be used in conjunction with upright supporting members and thereby be employed in a fence-like capacity. Furthermore, the polymer panel surface provides a suitable substrate for the attachment of wall board or gypsum for the interior wall of a building, and for the attachment of stucco or plaster for the exterior wall of a building or for a fence-type wall.
An example of a building wall form is disclosed in U.S. Pat. No. 4,924,641 issued on Nov. 15, 1990 to Gibbar. Gibbar's invention provides for pairs of polystyrene panels in which polystyrene blocks are used as spacers between the panels. The polystyrene blocks are integrally formed onto one of the panels, the other panel being glued onto the blocks to form a complete wall unit. The blocks set the thickness for the concrete that is poured between the panels. Blocks present at the ends of some pairs of panels extend beyond the edges of the panels in order to extend into, and thereby interconnect with, other laterally adjacent wall units. The wall units may be stacked vertically to give a desired wall height by means of T-shaped ties and straps. After insertion of reinforcement rods and appropriate bracing of the interconnected wall forms, concrete is poured into the interior spaces defined by the panels and blocks to give a monolithic wall structure.
Another application of polymer panels for use in building construction is revealed in U.S. Pat. No. 5,353,562 issued on Oct. 11, 1994 to Decker. Rather than using two panels to comprise a wall unit, Decker's invention employs individual polystyrene foam panels eight inches in thickness in which "troughs" have been routed or cut into both the top and side ends of the panels. The troughs are centered and are approximately six inches wide and six inches deep. Thus, the panels, when the top and side edges are viewed upon, have the appearance of being two, one inch panels spaced six inches apart. The panels may also be equipped with tongue and groove arrangements to permit the panels to interlock. When the panels are connected end to end, the vertical end troughs of adjacent panels create columnar spaces into which concrete is poured, after placement of reinforcing rods, to form concrete columns. The horizontal top troughs are similarly reinforced with rebar, filled with concrete, and troweled smooth. A second row of panels may be placed on top of the first and secured with spikes, which are placed in, and extend from, the wet cement in the top troughs. Thus, a structural skeleton comprised of concrete columns and beams is formed.
U.S. Pat. No. 5,184,808 issued on Feb. 9, 1993 to Vesper (U.S. Pat. No. 5,129,628 issued 14 Jul. 1992 to Vesper is substantially identical) shows polymer panels employed in a non-load bearing capacity for fence wall construction. Vesper's invention provides for expanded polystyrene or polyurethane panels that are formed with two vertical slots present at each panel end, the slots running substantially the height of a panel. The slotted panels fit onto steel I-beam posts having two pairs of opposing side flanges. The I-beam flanges fit into the vertical panel slots, thereby supporting the panels. The base of each post is embedded in a concrete footing, and a decorative aspect is provided to the panels by coating them with stucco.
While each of the foregoing inventions, and others of their genre, employ certain techniques that impart different advantages to wall form construction, all are more complex than is desirable to allow for the rapid and inexpensive construction of decorative, privacy type walls. In addition, such walls as presently made are very susceptible to damage from earth movement. Thus, the very substantial need still exists for a durable, modular type wall structure to which stucco and other decorative material may be applied, that can be constructed quickly and at a reduced cost, and that is resistant to earthquakes and other forms of earth movement.